Roberta Vinci into semi-finals

Roberta Vinci outlasted Kristina Mladenovic to reach the semi-final of a grand slam for the first time in her singles career with a 6-3 5-7 6-4 victory in a physical US Open quarter-final.

Italian Vinci, who at 32 is 10 years older than her opponent, sailed through the first set in just 27 minutes on Arthur Ashe Stadium, but saw Mladenovic fight her way back into the match in New York.

However, the Frenchwoman - who required medical treatment twice - ran out of steam when Vinci broke in an epic seventh game in the decider and the world number 43 powered through to win in a time of two hours and 32 minutes.

Vinci, who was handed a walkover into the quarters after Eugenie Bouchard's withdrawal, now faces either defending champion Serena Williams or her sister Venus in the last four.

The only break of the first set came in just the second game when a huge forehand from Vinci left Mladenovic out of position and she could only put the return into the net.

From there Vinci was able to effortlessly coast through her service games with the Italian dropping just six points on serve in the first set, and the opener was wrapped up when Mladenovic went long with a forehand.

Mladenovic limply surrendered serve to trail 2-1 in the second, but the match swung in the Frenchwoman's favour as she won three straight games breaking for a 4-2 lead with a huge forehand that Vinci had no answer to.

Back-to-back Mladenovic double faults handed the break back in game seven and she required medical attention after holding for a 5-4 lead, but Vinci was unable to capitalise and her opponent levelled the match with a thumping double backhand.

Vinci staved off three break points to hold for 2-2 in the decider, before making the breakthrough in an epic seventh game that lasted 15 minutes - stealing ahead with a fifth break point when Mladenovic went long when chasing down a drop shot.

Mladenovic had her left thigh taped up after that game. And the physical match took its toll as Vinci wrapped up the win when Mladenovic put a return into the net.